Not every S&P 500 constituent deserves to be in your portfolio. We see two stocks positioned for outperformance and one that should be avoided.

EQT (NYSE:EQT), the largest natural gas producer in the United States by daily volume, has delivered 15.3 percent annual revenue growth over the last ten years—consistent market share gains in a competitive sector. Its EBITDA margin expanded 20.6 percentage points over five years, reflecting operational leverage and scale. The company maintains a 30.8 percent free cash flow margin, providing substantial capital deployment flexibility.

At $52.63 per share (17.1x forward P/E), EQT trades at a reasonable valuation given its growth and cash generation. The operational strength and trajectory make this a compelling long-term buy.

Airbnb (NASDAQ:ABNB), the world's largest online marketplace for lodging, offers a different growth profile. Nights and Experiences Booked grew 9.3 percent annually, creating room for profitable cross-selling if the company develops complementary services. The 35.6 percent EBITDA margin demonstrates efficient operations and disciplined management. Operating leverage has amplified profits significantly in recent years. Strong free cash flow generation funds new investments or shareholder returns through buybacks and dividends.

At $166.09 per share (16.4x forward EV/EBITDA), Airbnb's valuation reflects its market dominance and financial discipline. We remain convinced of continued upside.

STERIS (NYSE:STE), by contrast, faces real headwinds. The infection prevention and sterilization services provider operates in healthcare—a sector where we demand stronger performance. Annual revenue growth of 7.4 percent over two years falls short of our healthcare standards. More troubling: adjusted operating margins have been flat for five years, signaling management's inability to optimize the cost structure. Weak returns on capital suggest inefficient fund allocation.

At $214.45 per share (18.4x forward P/E), STERIS trades expensively for a company showing neither growth nor margin expansion. Avoid this name.